Physiologic doses of cholecalciferol enable most hemodialysis patients to achieve recommended levels of vitamin D and other biochemical measures, reports a trial in the American Journal of Kidney Diseases.
The VitaDial study included 55 adult patients receiving maintenance dialysis whose 25-hydroxyvitamin D3 levels were less than 30 ng/mL, enrolled at two Belgian centers. In an initial randomized phase, patients were assigned to receive 13 weeks of oral cholecalciferol, 25,000 IU per week, or placebo. This was followed by a 26-week open-label phase, in which patients received individually prescribed cholecalciferol, based on National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines. The main outcome of interest was the percentage of patients with 25(OH)D levels of 30 ng/mL or higher at the end of the randomized phase.
At 13 weeks, 61.5 percent of patients in the cholecalciferol group had 25(OH)D levels of 30 ng/mL or higher, compared with just 7.4 percent of the placebo group. Cholecalciferol was also associated with higher levels of 1,25-dihydroxyvitamin D3 (1,25[OH]2D), 22.5 versus 11 pg/mL; and a higher likelihood of normal calcium levels, 76.9 versus 48.2 percent.
There was no significant difference in hypercalcemia incidence or in levels of phosphate and intact parathyroid hormone. Among patients from the placebo group, open-label treatment did not alter the percentage reaching the 25(OH)D target level.
Current guidelines recommend a 25(OH)D level above 30 ng/mL in patients receiving maintenance hemodialysis, but they do not address how to achieve that target. The new study finds that 13 weeks of once-weekly oral cholecalciferol is an “effective, safe, inexpensive, and manageable” approach to increasing 25(OH)D and 1,25(OH)2D levels. The authors note that although their study did not address hard clinical endpoints, it found lower rates of falls and fractures in the cholecalciferol group [Massart A, et al. Biochemical parameters after cholecalciferol repletion in hemodialysis: results from the VitaDial randomized trial. Am J Kidney Dis 2014; 64:696–705].